Substituted 2-(3&#39;-methyl-2&#39;-buten)yl-4-hexenal odorant compositions

ABSTRACT

wherein R1, R2 and R3 each represent a hydrogen atom or a methyl group.   The novel aldehydes have the following general formula

United States Patent [191 Lamparsky et al.

[ Dec. 16, IS

[ SUBSTITUTED 2- 3 -METl-IYL-2 -BUTEN YL-4-HEXENAL ODORANT COMPOSITIONS [75] Inventors: Dietmar Lamparsky,

Wangen-Dubendorf; Jean-Pierre Calame, Fallanden, both of Switzerland [73] Assignee: Givaudan Corporation, Clifton, NJ.

[22] Filed: July 30, 1974 [21] Appl. No.: 493,002

Related US. Application Data [62] Division of Ser. No. 323,l90, Jan. 12 1973,

abandoned.

[30] Foreign Application Priority Data Jan. 21, 1972 Switzerland 901/72 [52] US. Cl. 252/522 [51] Int. Cl. CllB 9/00; A6lK 7/00 [58] Field of Search 252/522 [56] References Cited UNITED STATES PATENTS 3,391,192 7/l968 Zuech et al 260/601 OTHER PUBLICATIONS Chem. Abstracts, Vol. 50 5568, 1956.

Steffen Arctauder, Perfume and Flavor Material: Natural Origin, Elizabeth, NJ. (USA) 1960, 296-299.

Primary ExaminerVeronica OKeefe Attorney, Agent, or FirmThomas Cifelli, Jr.

[57] ABSTRACT The novel aldehydes have the following general mula wherein R R and R each represent a hydro atom or a methyl group.

8 Claims, No Drawings SUBSTITUTED 2- 3 .-METHYL-2 -BUTEN YL-4-I-IEXEN AL ODORANT COMPOSITIONS This is a division of applicationSer. No. 323,190, filed Jan. 12. 1973, now abandoned.

FIELD OF THE INVENTION Aliphatic. diolefinic aldehydes having interesting olfactory properties.

RELATED APPLICATION This application claims priority from the copending Swiss application, No. 907/72. filed Jan. 21. 1972.

SUMMARY OF THE INVENTION A preferred class of aldehydes of formula I comprises those of the general formula CH1; R zi wherein R and R have the significance given earlier.

Acoording to the process provided by the present invention, the aldehydes of formula I hereinbefore are manufactured by reacting an acetal of the general formula OR R 3 wherein R and R have the significance given earlier and R represents an alkyl group containing from I to 6 carbon atoms, or an enol ether of the general formula wherein R, R and R have the significance given earlier, with an alkenol of the general formula wherein R, has the significance given earlier, in the presence of an acidic catalyst.

DETAILED DESCRIPTION OF THE INVENTION 2 formula III in which R represents a hydrogen aton the methyl group. or

b. by reacting an alkenol of formula IV in whicl represents a methyl group (i.e. 3-methyl-l-pente1 01) with an acetal of formula II or an enol ethe formula [II in which R represents a hydrogen atoi The reaction of an alkenol of formula IV with acetal of formula II or an enol ether of formula Ill be carried out in a manner known per so (see. for ample. Swiss Pat. specification No. 416596). Thus the acidic catalyst there can be used. for exampl mineral acid such as sulphuric acid or, especially, pl phoric acid. However, there can also be used a str organic acid such as oxalic acid, trichloroacetic a p-toluenesulphonic acid, an acidic salt such as. example. potassium bisulphite or a Lewis acid suc boron trichloride. boron trifluoridc or Zinc chlorid According to a particularly preferred embodimei pyridine hydrohalide. especially pyridine hydroc ride. is used as the acidic catalyst since in this cast aldehyde of formula I is obtained in particularly g yields. The concentration of this catalyst in the reac mixture expediently amounts to about 2-5 wt.7c. e cially to about 3-4 wt.'7c. corresponding to a cat; amount of ca 1/10 molar equivalent. based on amount of acetal or enol ether starting material as The reaction using this catalyst is preferably car out in the presence of a solvent. Especially suit solvents are aromatic hydrocarbons such as. for ex ple, benzene. toluene or xylene. However. high-b0 petroleum ethers or chlorinated aliphatic hydrocarl such as, for example. methylene chloride, ethy chloride or trichloroethylene, can also be used. A ticularly preferred solvent is toluene.

In this preferred embodiment the reaction is prel bly carried out under atmospheric pressure. The at of formula II or the enol ether of formula III or a ture of such an acetal and enol ether is. for exan heated in the presence of the alkenol of formula IV the catalyst in one of the solvents mentioned earlir the reflux temperature of the reaction mixtureanc alcohol ROH formed during the reaction is cont ously distilled off from the reaction mixture (eg; a azeotrope with the solvent used). Preferably, the volume of the reaction mixture as well as the orig ratio of the reactants is approximately maintainer the addition of solvent and/or alkenol (which can off in small amounts at the same time as the alk ROH liberated during the reaction distils off). optimal (mol) ratio of acetal offormula II or enol & of formula III to alkenol of formula IV amount about 1:15. The solvent should. for example, be 1 ent in amounts (by weight) which correspond to a double the amount of acetal (or enol ether) an kenol.

In order to achieve optimal yields, the progress 0 reaction is expediently followed by the removal of ples which are analysed (e.g. by gas-chromatograr the heating being discontinued as soon as the acet enol ether reactant has reacted to around 95 per in this case the yield of aldehyde of formula I amount to percent or above. In general, the real duration necessary for this is about 20 hours.

The resulting aldehyde of formula I can be iso from the mixture of the reaction products in a me known per se, expediently by fractional distilla Advantageously, the catalyst is neutralised beforl distillation by the addition of an inorganic or or;

agent such as sodium acetate. caustic soda. socarbonate, ammonia. a tertiary amine such as iylamine or pyridine, etc and thereafter removed the reaction mixture if desired. ofar as they are not known. the acetals of formula d the enol ethers of formula III can be prepared rding to methods known per se (see. for example, an Pat. specification No. 650657). e aldehydes of formula I provided by the present ition. particularly those of formula la. possess :sting odorant properties. As will be evident from ollowing descriptions. their character can generae denoted as hesperidin-like and green. The quite ordinary fresh character is also of significance. fragance character is peculiar to the aldehydes of ula I and, in particular, to those of formula Ia as with lower and higher homologues have shown. -Dimethyl-2-[3 -methyl-2 -buten]yl-4-hexenal: aridin-like (lemon), green. spicy, fruity and floral. aldehyde is well suited as-a modifier of the topof floral and/r green compositions. It increases iiffusibility of, for example, woody and chypre )ositions. vIethyl-2-[ 3 '-methyl-2 '-buten]yl-4-hexenal: heslin-like, very fresh, natural-green, floral (of roses), use and lavender. This aldehyde is especially suitfor floral compositions such as muguet, lilac and :nia to which it conveys lightness" and a pro- .ced diffusibility. However, the character of fouand animal compositions are also improved by 18 of this aldehyde. vlethyl-2-[ 3 '-methyl-2 '-buten]yl-4-heptenal: simithe last-mentioned aldehyde, but with a fruitier greener character. -Dimethyl-2-[ 3 '-methyl-2 '-buten]yl-4-heptenal: eridin-like, green, somewhat woody. Y I l the basis of their interesting olfactory properties, h stand out from a whole series of structurally ed aldehydes, the aldehydes of formula I can acingly be used as odorants; for example in perfumor the manufacture of odorant compositions such rfumes or for perfuming products of all kinds such or example, soaps, washing agents, detergents, sols or other cosmetic products such as salves, milk, make-up, bath salts, etc. e concentration in which the aldehydes of formula used can vary within wide limits depending on the ose of use, for example between about 0.1 and t wt.%. For odorant compositions the preferred entrations lie in the range of from about 1 to about 7:. e following Examples illustrate the process pro- 1 by the present invention:

EXAMPLE 1 D g of 2-methyl-3-buten-2-ol, 2 g of crystalline phoric acid and 500 g of 2,5-dimethyl-4-hexenal .ylacetal are placed successively, with stirring, in a ble reaction vessel and the mixture is then held at x for 5 hours while gassing with nitrogen. In so the temperature falls from 107C to 102C. The x condenser is then replaced by a column having a lation bridge and the ethanol formed is distilled off y in the course of 6 to 8 hears. In so doing, the er'ature rises continuously to 140%. At this temftlf'el; with the same rate of heating, 'the. distillation is to proceed more rapidly. the new temperature g off (formation of isop're'ne ff'ofn methylbutenol).

.ory) of boil A total of 425 ml of distillate are collected. After completion of the reaction, the reaction product is cooled, diethyl ether is added and *the ethereal solution is washed with sodium hydrogen carbonate solution and water and then dried. After distilling off the solvent, the crude product is fractionallydistilled in a vacuum. There are obtained 240 g (49% of theory) of 2,5- dimethyl-2-[3'-methyl-2'-buten]y l-4-hexenal of boiling point ll5l 17C/2O mmHg; 11 1.4688.

EXAMPLE 2 8.6 g of 2-methyl-3-buten-2-ol. 0.1 g of phosphoric acid and 30.8 g of l-ethoxy-2,5-dimethyl-1,4- hexadiene are mixed in a suitable autoclave. After pressurisation with nitrogen (5 kg/cm"), the autoclave is placed in an oil-bath (preheated to 165C) and heated for 1.5 hours to an internal temperature of 165C 5C. In so doing, the pressure reaches maximally 10.4 kg/cm After chilling the autoclave and discharging the excess pressure, the reaction mixture is treated with ca 1 ml of triethylamine and fractionally distilled in a vacuum. There are obtained 10.6 g of 2,5-dimethyl-2-[3-methyl-2-buten]yl-4-hexenal (54 percent of theory) of boiling point 1l2ll3C/13 mmI-Ig; n 1.4680. The purity according to gaschromatography is ca 85%. i

EXAMPLE 3 400 g of 2,5-dimethyl-4hexenal diethylacetal. 25 8 g of 2-methyl-3-buten-2-ol, 1000 g of toluene and 24 g of pyridine hydrochloride are placed in a reaction vessel provided with a thermometer. dropping funnel and a 40 cm Vigreux column having a distillation bridge. The mixture is heated to boiling and the toluene/ethanol azeotrope, which contains some 2-methyl-3-buten-2-ol,

'is distilled off slowly over the Vigreux column. Fresh toluene (a total of 3 kg) is allowed to flow in through the dropping funnel at thesame rate as the solvent distils off. In addition, after 7 hours, a further 43 g of 2-methyl-3-buten-2-ol are added and the distillation is continued up to a total duration of 20 hours. After this time, ca percent of the starting materials have reacted. The addition of fresh toluene is stopped and the solvent remaining in the reaction flask is removed as far as possible by distillation. The reaction mixture is treated with 16 g of sodium acetate and fractionally distilled in a vacuum. There are obtained 290 g (74% of theory) of 2,5-dimethyl-2-[ 3 -methyl-2 -buten yl-4- hexenal of boiling point 1 12C/l2 mmI-Ig.

EXAMPLE 4 In an analogous manner to that described in Example 1, a mixture of 171 g of 2-methyl-3-buten-2-ol, 2 g of crystalline phosphoric acid and 398 g of 5-methyl-4- hexenal diethylacetal is held at reflux for 5v hours with stirring and gassing with nitrogen. The ethanol formed is subsequently distilled off slowly through a column until the temperature in the flask reaches l33135C. This temperature is attained after about 6 hours, 285 g of distillate then being present. The working up is carried out in an analogous manner to that described in Example 1. There are obtained g of 5-methyl-2- [3-methyl-2buten]yl-4-hexenal (28 percent of thei i ing point l02 l 14C/1O mmI-Ig; n

EXAMPLE 5 I -continued In an analogous manner to that described in Example parts by wcig 3, 400 g of 5-methyl-4-hexenal diethylacetal. 275 g of phen \'l t-lh l fUl'lTIZllC all 2-methyl-3-buten-2-ol. 1000 g of toluene and 25 g of 5 E P ll pyrldlne hydrochlorlde are reacted for 7 hours. A furd L ther 50 g of 2-methyl-3-buten-2-ol are added and the P l l phen \l eth \l isobut rate 50 react on stopped after -Ohours (total duratlon). The Cinnumic JICUhOI symhv worklng up is carrled out ln an analogous manner to h} .lro.\ citronellul 70 that described in Example 3 after the addition of g Phfin)" l Bfl of sodium acetate to the crude product before the distillation in a vacuum. There are obtained 180' g (46 percent of theory) of 5- methyl-2-[3-methyl-2'-buten- ]yl-4-hexenal.

The 5-methyl2-[ 3 -methyl-2 '-b uten ]yl- 4-h x 5 imparts to the composition an exceptional finene EXAMPLE 6 natural freshness.

In an analogous manner to that described in Example EXAMPLE B 3, 300 g of 2,5-dimethyl-4-hexenal diethylacetal are reacted with 225 g of 3-methyl-l-penten-3-ol in the Composition of the chypreii type presence of 17.4 g of pyridine hydrochloride and 1000 20 ml of toluene. After 12 hours, a further 75 g of 3methpans w yl-l-penten-3-ol are added. The reaction is complete 1 7 i after hours (total duratlon). After the addltlon of 13 5: 3:32: l3 math) bu'enl 60 g of sodium acetate to the crude mixture, the reaction blibanurn resinoid 10 product is fractionally distilled in a vacuum. There are methylnonylacetaldehyde l71 2t) obtamed 160 g of y y 2.6.l(J-trimethyl-9undecen-l-al (1071) l() lyl-4-heptenal of boillng point l57l58C/60 mmHg; undecl'lenflldehyde I 1071 20 l 4690 -yundecalactone 1'7: l() n!) vetiver oil Bourbon 2U sandalwood oil East lndies 4U EXAMPLE 7 30 patchouli oil 1.1.4.44 rrll 'l-6- m -l-7-- r -l- In an analogous manner to that descrlbed ln Example -l z 3ajeigilidrimagmlluleni i 40 3, 150 g of 5-methyl-4-hexenal diethylacetal are rea Oak demlmised llnalool 4t) acted wlth 130 g of 3-methyl-l-penten-3-ol 1n the presbergamoue on ence of 10.5 g of pyridine hydrochloride and 450 ml of hydroxycitronellal 14o toluene over a period of 30 hours, a further 25 g of 35 $2 2, 35 3-methyl-l-penten-3-ol being added after the first l5 phenyl ethyl alcohol IOU hours. After working up in accordance with Example 3, 3

there are obtained 75.7 g of 5-methyl-2-[3-methyl-2'- buten]yl-4-heptenal of boiling point 125-l26C/ l5 in phthulic ilClLl dielhyl ester mmHg; n 1.4675. 40

The starting materials used in the various Examples The y be Prepared as follows: nal imparts to the chypre composition freshnes starting material source n b.p.

Z-methyl-Ii-buten-Z-ol 3-methyl-l-pentem3-ol l ethox .'-2.5-dimethyll .4-hexadiene 5-methyl-4hexanal diethyl-acetal 5-methyl-4Zhexem 1 -al The following Examples illustrate a typical odorant fruity character and, at the Same timei h diff composition containing the aldehydes provided by the 55 increased invention: What we claim is: g

EXAMPLE A 1. An odorant compositloh Which contalfil essential odour-imparting ingrediefit an olfz Composltlon of the hyacmth type' effective amount of an aldehyde of the gfiral f parts by weight CHO 5-methyl-2-[3'-methyl-2'-buten]yln Ame-Kenn! R=, H.,c c=cH-cl-l 'i cll cll lf ell :-R phenylacetaldehyde (5071) 5 I indole (10%) 5 CH3 RI (H skatole 1'71 5 galbanum essence 10 I hydm'fpaldchyde \lvherein R R and R each represent a hya'mg 6U eno g 30 br a methyl group.

phenyl ethyl cinnamate 1 odor-ant composition according to claim 1 :ontains an aldehyde of the general formula:

CHO

CH R. 1:

1 R and R. each represent a hydrogen atomv or yl group. n odorant composition according to claim 2 :ontains 2.5-dimethyl-2 -[3'-mcthyl-2-buten]ylml.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 5,926,859 Dated December 1975 Dieter Lamparsky et al.

Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the Title page, under "Other Publications", "Steffen Arctauder" should read Steffen Arctander Column 1, formula Ia should read as follows:

Column line Al, "distils" should read distills Column T, line #6, "percent" should read symbol Column LP, line 66, "percent" should read symbol Column 5, line 15, "percent" should read symbol Signed and Scaled this Twentieth Day of July 1976 [SEAL] Arrest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner ofPatenls and Trademarks 

1. AN ODORANT COMPOSITION WHICH CONTAINS AS AN ESSENTIAL ODOUR-IMPARTING INGREDIENT AN OLFACTORILY-EFFECTIVE AMOUNT OF AN ALDEHYDE OF THE GENERAL FORMULA:
 2. An odorant composition according to claim 1 which contains an aldehyde of the general formula:
 3. An odorant composition according to claim 2 which contains 2, 5-dimethyl-2-(3''-methyl-2''-buten)yl-4-hexenal.
 4. An odorant composition according to claim 2 which contains 5-methyl-2-(3''-methyl-2''-buten)yl-4-hexenal.
 5. A method of imparting an odour to materials which comprises applying thereto or incorporating therein an olfactorily effective amount of an aldehyde of claim
 1. 6. A method according to claim 5, wherein an aldehyde of claim 2 is used.
 7. A method according to claim 6, wherein 2,5-dimethyl-2-(3''-methyl-2''-buten)yl-4-hexenal is used.
 8. A method according to claim 6, wherein 5-methyl-2-(3''-methyl-2''-buten)yl-4-hexenal is used. 